Hydraulic air-compressor.



No. 643,962. Patented Feb. 20, |900.

v J. C. HOWARD.

HYDRAULIC AIR GUMPRESSOR.

rA'pplicanio-n med ont. 24. 1899.,

(No Model.)

W/TNESSES i. i?? A Trop/v5 me,

THE u nnms PETERS co.. PHOTO-Limo., wAsHmamN. D. cy

UNITED. STATES PATENT OFFICE.

JESSE c. HOWARD, oEcoLUMBUs, onto.

HYDRAULIC AIR-COM PRESSOR.

SIECIFICATION forming part of Letters Patent No. 643,962, dated February20, 1900.

Application iiled October 24, 1899. Serial No.,734,648. (No model.)

To all whom. t may concern:

Be it known that I, JESSE C. HOWARD, a citizen of the United States,residing at Columbus, in the county of Franklin and State of Ohio, haveinvented certain. new and useful Improvements in I-IydraulicAir-Compress ors; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

The object of my invention is to provide an improved construction inwhich leakages, rapid wear or destruction of packings, deadcenters,noise, and other objections common to apparatus of this kind now uponthe market are overcome.

The accompanying drawing, showing one embodiment of my invention,presents a central vertical sectional view taken on a plane through thesupply-inlet and the outlet openings, eXcept as to the cut-oft tube,which is shown partially in elevation and partially in section, andtheair-compressor cylinder and its contained parts are broken out at twoplaces.Y

1 designates the base; 2, the casing containing thehydraulically-operated pistons and valves; 3, the air-compressorcylinder; 4, a cap for the air-compressor cylinder, in and upon whichare the usual or any approved devices for admitting air to theair-compressor and checking it after it is compressed.

The casing 2 has water-inlet 5 and wateroutlet 6, ports with valve-seats7 and 8, a passage 9, connecting inlet 5 through the supply-port atvalve-seat 8 with the chamber of air-compressor cylinder 3. The casing 2also has just below the inlet-port 5 a cylindrical piston-chamber 10 andbelow this a larger cylindrical piston-chamber 10, the latter connectedwith outlet 6 by a passage 11. The chamber of cylinder 3 communicateswith outlet 6 through an exhaust-port having valveseat 7. The sides ofthe chambers 10 and 10a are smooth and unbroken by ports or orificeswhere the pistons hereinafter described play.

The main-valve stem I prefer to make of two parts 12 and 12a, threadedtogether, so as to permit adjustment of the valves thereon with respectto each other. This valve-stem has an axial opening, as indicated at12b, en-

larged'in its lower portion, as indicated at 12. The valve-stem has twovalves 13 and 13a, that tit the seats 7 and 8 of the exhaust and supplyports, respectively; but these valves are located at such distance apartthat one of the ports may be closed while the other is open. Thevalve-stem reciprocates in an opening in a web between the seats 7 and8, and to make this place water-tight I provide a cup-leather or packing19, held by a nut 19a. The outer side of the lower end of the portion 22of the valve-stem is furnished with a piston composed of cup-leather orpacking 14, supported on and by a flanged ring 14a. This piston tits andworks in the chamber 10. Below on the stem and fitting in the chamber10a is another piston of larger diameter composed ot' a cup-leather orpacking 15, held between a ring 15a and a flanged nut 15b, threadingonto the lower end of the portion 12. In the enlarged portion 12c of theaxial opening in the valve-stem are two small cylinders 16 and 17 withcup-leathers or packings 16, 17a, and 17h, arranged at the ends of andbetween the two cylinders, as shown, all of which cylinders andcup-leathers or packings are held together and in place between washer17c at the upper end and a nut 18, threading into the lower endof theopening 12". Within the axial opening of the valve-stem, and in whichthe cup-leathers 16a, 17a, and 17h are fitted, is the cut-olf tube 20.This tube is closed at its upper end and open at its lower. It is alsoprovided with an opening or openings 20d.

The valve-stem and cylinder 16 are provided with openings 23 and 24,respectivelyL to admit water from above the cup-leather 14 into the tube20 when the openings 2Od therein are opposite cylinder 16, and the ring14 and valve-stem and cylinder 17 are provided with openings 21 and 22below that cup-leather, but above cup-leather 15, to allow water toexhaust from below that cup-leather through tube 2O and passage 11, whenthe openings 2Od are opposite cylinder 17.

In the position of the parts within the casing 2, as shown in thedrawings, the water under pressure through inlet 5 has access to thelower end of the usual weighted air-compressing piston in the cylinder 3and to the upper side of the piston in the chamber 10. This pressureforces the valve 13 down on its IOO ICL

seat 7, closing the port there, and lifts the air-compressing piston. .Iust before the aircompressing piston has risen to its limit the cut-offtube 2O is lifted by the nut 20b in the tube 2Oc of the air-compressingpiston, so as to bring' the openings 201 into communication with theports 23 and 24. This shifting of the tube 20 allows the pressure of thesupply to act on the under side of the piston in the chamber 10, Which,being of larger diameter than the piston in chamber 10, preponderatesand forces the valve-stem up and the valve 13 out of its seat and closesthe valve 13:L upon its seat 8. The water in the air-compressor chamber3 then discharges through the port at seat 7, the air-compressordescending by gravity. At the proper time the upper end of the tube 2OCstrikes the upper end of the rod 2Of of the tube 20, or, if preferred, acap 203 on the stem, shifting the openings 20d to a position below thecup-leather 17 and again into communication with the ports 21 and 22.This shifting of the tube 2O cuts off the pressure from the under sideof the piston in the chamber 10a and allows the pressure on the valve inchamber 10 to again close the valve 13 ou its seat When the operation isrepeated. Then the valve-stem is forced down by pressure on the valve inchamber 10, the water below the piston in chamber 10 exhausts throughopenings 20d, 21, 22, 11, and discharge 6.

12d is an annular cushion to take the impact of the air-compressingpiston at the end of its descent.

XVhat I claim, and desire to secure by Letters Patent, is-

1. In a hydraulic air-compressor, the casing 2 having supply and exhaustports with valve-seats 8 and 7, respectively, and pistonchambers 10 and10, a valve-stem having valves for the seats 8 and 7, pistons in theMaese chambers 10 and 10, With means for auto-y matically changing thepressure from one pistou to the other, substantially as described.

2. In a hydraulic air-compressor, the casing 2 having supply and exhaustports with Valve-seats 8 and 7, respectively, piston-chambers 10 and 10,a valve-stem having valves for the seats 8 and 7 and pistons for thechambers 10 and 10, a tubular cut-olf valve reciprocating Within saidvalve-stem provided With openings for admitting and cutting o thepressure-supply to the piston-chamber 10, substantially as shown anddescribed'.

3. The casing provided with supply and exhaust ports and piston-chambers10 and 10, a valvestem having valves for the supply and exhaust ports,separate pistons for the chambers 10 and 10a, openings in saidvalvestem, a cut-off'tube in said stem adapted to alternately admitwater to and exhaust water from the chamber 10, substantially asdescribed.

4. In a hydraulic air-compressor, the casing 2 having supply and exhaustports with Valve-seats 8 and 7, respectively, piston-cham; bers 10 and10, and outlet 6, a valve-stem having Valves for the seats 8 and 7,pistons for chambers 10 10, openings 23 and 2l communicating,respectively, with chambers 10 10, cylinders 16 and 17 each providedwith au opening to register with openings 23 and 21 fitted Within thevalve-stem, and a cut-olf tube reciprocating within the valve andcylinders 16 and 17, substantially as shown and for the purposedescribed.

In testimony whereof I aix my signature in presence of two witnesses.

JESSE C. I-IOVARD.

Witnesses:

GEORGE M. FINCKEL, THEoDoRE WEYANT.

